1. Field of the Invention
The present invention relates to a sound collection environment deciding device for deciding whether the sound collection was performed in air or in water, an electronic appliance having the same (e.g., an imaging apparatus, an IC Recorder or the like), and a sound collection environment deciding method. Furthermore, the present invention relates to a sound processing device equipped with the sound collection environment deciding device, for processing an audio signal of sound collected in water, an electronic appliance having the same, and a sound processing method.
2. Description of Related Art
Conventionally, various types of imaging apparatuses are proposed, which has a waterproof structure for imaging in water and is equipped with an imaging environment deciding device for deciding whether the imaging environment is in air or in water.
For instance, there is an apparatus that includes a pressure sensor attached to the apparatus main body for deciding whether or not it is in water so as to decide the imaging environment. In other words, this apparatus uses the pressure sensor for deciding whether or not it is in water as an imaging environment deciding device for deciding whether the imaging environment is in air or in water.
In addition, there is another apparatus in which in-water deciding means including light projecting means and light receiving means decide whether or not it is in water based on an amount of light received by the light receiving means after projected by the light projecting means, utilizing a difference of light refractive index between water and air, so as to decide the imaging environment. In other words, this apparatus uses the in-water deciding means including the light projecting means and the light receiving means as the imaging environment deciding device for deciding whether the imaging environment is in air or in water.
However, since the above-mentioned imaging environment deciding device needs the additional special component for deciding the imaging environment such as the pressure sensor or the in-water deciding means including the light projecting means and the light receiving means, there is a problem that it is difficult to reduce the size or the cost of the apparatus main body including the imaging environment deciding device. In addition, there is another problem that it can be applied only for imaging and recording but for reproducing the imaged data since it can decide only in the period while the apparatus main body including the imaging environment deciding device is in water.
In addition, since sound collection characteristics in water are substantially different from sound collection characteristics in air, an audio signal of sound collected in water by using an electronic appliance is substantially different from an audio signal of sound collected in air. Therefore, there is a problem that an audio signal that is different from the user's intention may be generated in such a way that the sound is very hard to listen or a grating sound when the audio signal of sound collected in water is reproduced.